Technical Field
The present invention relates to a sheet tray, in which a plurality of stacked sheets may align with a predetermined position, and to an image forming apparatus having the sheet tray.
Related Art
An image forming apparatus, e.g., a multifunction peripheral device and a printer, may be equipped with a sheet tray that feeds sheets to an image forming unit. The sheet tray may include a lifting plate to uplift the sheets stacked thereon to feed the sheets, from a topmost one of the sheets, one after another to the image forming unit. The sheet tray may have a sheet guide including a side guide and a rear guide, which may be arranged to contact lateral edges and rearward edge of the sheets. The side guide and the rear guide may be slidable along a bottom of the sheet tray so that the side and rear guides may be moved to fit with the edges of the sheets and the sheets may be placed at a predetermined position in the sheet tray.
The sheet guide may include a locking device with a lever, which may be operated by a user and pivot about a pivot shaft, and a stopper, which may move along with the pivoting motion of the lever. The pivot shaft may be fixed to the sheet tray. For example, when the lever is moved to pivot about the pivot shaft, the stopper locked to a bottom plate of the sheet tray may be uplifted to be separated from the bottom plate so that the sheet guide may be released from the lock to be movable. Thus, the pivoting motion of the lever may be converted into a linear motion to uplift the stopper. In order to convert the pivoting motion to the linear motion, the locking device may include an L-shaped piece that may be pivotably attached to the pivot shaft at a bended corner and extend from the pivot shaft to the stopper. Further, in order to uplift the stopper for a substantial amount from the bottom plate, the L-shaped piece may have a substantial length. Therefore, the sheet guide may require a substantial volume of space, in which the L-shaped piece is movable. Specifically, thickness, e.g., a volume in a direction orthogonally to a planar direction, of the sheet guide may tend to increase so that the L-shaped piece may pivot therein. With the increased thickness, reduction of an overall volume of the sheet tray may have been difficult.